® Belching, Bloating and Flatulence ® GastroenteroloGy department By Larry Szarka, M.D., Mayo Graduate School of Medicine, Rochester, Minnesota and Michael Levitt, M.D., Veteran Affairs Medical Center, Minneapolis, Minnesota What are the Gas related symptoms? The air that is swallowed and not removed by belching will pass through the digestive tract and eventually pass as flatus from Belching, or burping refers to the noisy release of air or gas the rectum. In normal people, about 50% of the gas passed from from the stomach through the mouth. Unpleasant abdominal the rectum comes from swallowed air, and this amount can fullness or distention is called bloating. Flatulence is the pas- increase significantly in those individuals who swallow air ex- sage of excessive amounts of intestinal gas, or flatus, through cessively. Surprisingly, most people who experience excessive the anus. bloating and flatulence do not swallow or produce excessive gas. In these individuals, it seems that the movement of swal- hoW Common are Gas symptoms? lowed air, from the stomach toward the rectum, is much slower As much as 7% of the general population complain of excessive than normal. Additionally, the gas may sometimes move the or bothersome belching, and 11% report frequent bloating. wrong way, returning to the stomach. So, in spite of the fact that Normal people pass gas (flatus), on average, ten times each the amount of gas may be normal, people can experience bloat- day. Passage of gas up to twenty times daily is still considered ing and “gas” because the gas is not moved efficiently, and it normal. may accumulate, causing discomfort from the increased stretch- ing of the bowel walls. What are the Causes of Gas symptoms? hoW do some foods lead to exCess Gas? There are several important factors that influence gas related symptoms. These include the amount of air that is swallowed; Some people have difficulty digesting certain foods completely. the efficiency with which the gastrointestinal tract moves and This can lead to partially digested food passing from the small expels the air or gas; and the amount of gas that is produced by intestines to the colon. There are a large number of bacteria in the bacteria living in the colon that act on incompletely digested the colon that will readily “digest” the food further and produce food. There are also individual differences in sensitivity or toler- gases in the process. Foods that contain certain sugars that are ance to normal amounts of retained gas or the passage of a very difficult for most people to digest include the well-known normal amount of flatus. gas-forming foods such as baked beans, lima beans and lentils. Most people also have difficulty properly digesting commonly Can a person SwalloW too muCh air? added sweeteners such as fructose and sorbitol. Some people (particularly adults of Asian, African and Southern European It is clear that some individuals swallow too much air into the descent) have difficulty digesting lactose (milk sugar) because stomach. Eating quickly, gulping food or beverages, and other they do not make enough of the enzyme, lactase, which is need- habits such as drinking through a straw, chewing gum, sucking ed to breakdown lactose. If there is a large amount of lactose in on hard candy or wearing loose fitting dentures may contribute their diet, then the incompletely digested lactose will pass to the to excessive air swallowing. People also swallow more frequent- colon where bacteria break it down and produce gas. It is also ly and swallow more air when they are nervous. Air can also be thought that there are differences between individuals in their swallowed and released voluntarily as many people are able to sensitivity to intestinal stretching from gas, and their tolerance belch at will. In some people, excessive belching has become a for gas related symptoms. The sensitivity of the gastrointesti- learned behavior, or habit, that initially may have been associat- nal tract and the severity of symptoms tend to increase as the ed with some relief of indigestion symptoms, but now continues amount of stress increases. almost unconsciously. ©The American College of Gastroenterology | 6400 Goldsboro Rd., Suite 450, Bethesda, MD 20817 | P: 301-263-9000 | F: 301-263-9025 | www.acg.gi.org 1 [10562 7/10] THEPORTLANDCLINIC.COM Can Certain mediCations Cause exCess Gas? What treatments are available for the Gas-related symptoms? There are some prescription medications that purposefully in- hibit digestive enzymes (e.g. acarbose) and others that contain Sometimes excessive belching is associated with gastroesopha- indigestible sugars (lactulose and sorbitol) to accomplish their geal reflux disease (GERD), and treatment of this condition may intended effect. These medications will often cause gas-related alleviate bothersome burping. Anti-gas medications, such as symptoms. simethicone, are generally useless for excessive belching. Lifestyle modification such as avoidance of: rapid eating, Can exCess Gas mean there is a serious problem? chewing gum, carbonated beverages and stopping smoking are often recommended but the response is variable. When simple Rarely, patients can have a serious underlying disease of the reassurance and lifestyle modifications are not satisfactory, digestive tract, such as celiac disease (gluten intolerance), then psychological treatments such as relaxation therapy or dumping syndrome or pancreatic insufficiency that is the cause behavioral therapy are currently the most useful approaches. of their gas symptoms. These conditions may lead to improper digestion of food and result in excessive diarrhea, flatulence and Bloating and flatulence are sometimes related to constipation, finally, malnutrition and weight loss. and treating the underlying condition may be helpful. After other conditions, such as lactose intolerance, have been exclud- When should you see a doCtor about belChinG, ed, a low gas-forming diet should be recommended. The diet bloatinG or flatulenCe? excludes poorly digested foods such as the Brassica vegetables (brussel sprouts, turnip, rape, mustard and cabbage), as well By themselves, gas-symptoms are not worrisome or indicative as beans and lentils. Foods (including any drink, candy, gum of any underlying serious condition. A visit to the doctor may be or breath freshener) that contain sorbitol and added Buctose helpful if the symptoms are very bothersome and there are other should also be avoided. Fiber supplements and a high fiber diet associated symptoms that may benefit from further testing and can aggravate bloating symptoms, and should be discontinued if or treatment. Symptoms that should be further evaluated by a there is no benefit. A diet containing rice flour is fully absorbed doctor include abdominal pain, vomiting, diarrhea, constipation, in the small intestines and so produces the least amount of gas. weight loss, bleeding from the gastrointestinal tract and some- There are several over-the-counter medications to treat gas- times heartburn. related symptoms including simethicone, activated charcoal and Currently, there are few clinical tests (other than the history beano. Unfortunately, none of these products are very effective. obtained from the patient and a physical examination) that are used to further assess gas symptoms. In some cases, endoscopy (the insertion of a small lighted flexible tube through the mouth into the esophagus and stomach) may be helpful if ulcer disease or reflux disease is suspected, or sigmoidoscopy or colonoscopy (insertion of a similar tube into the rectum and colon) if there are associated changes in the bowel patterns. An x-ray of the abdo- men may be performed if blockage of the intestines needs to be excluded. Sometimes lactose intolerance should be assessed with a trial of a lactose free diet for two weeks, or with a special blood or breath test. There are also simple blood tests available to screen for celiac disease (gluten sensitivity) if there are other features to suggest this disorder. ©The American College of Gastroenterology | 6400 Goldsboro Rd., Suite 450, Bethesda, MD 20817 | P: 301-263-9000 | F: 301-263-9025 | www.acg.gi.org 2 [10562 7/10] THEPORTLANDCLINIC.COM.